Lifting jack



J. A. CHEAPE LIFTING JACK May 24, 1932.

2 Sheets-Shet 1 Filed Oct. 6, 1927 y 24, 1932- J. A. CHEAPE LIFTING JACK Filed Oct. 6. 1.927

Patented May 24, 1932 seeelei mm ALBERT. Q'HEME, or GEAREOTTESNILLE, VIRGIN-m] l 'LIFTING JACK I My-i nventi om relates to an improvement in" lifting jaeks'. l V n v The primary Objfifi of this -wentior is to provide a: quick-acting jack, one-that will re- "TEE spend instantly te pressure "upon the part to heli fted or to which the ack i's-te he applied, causing the base or lower portion: ofi'the faickjtodrop to the floor or ground; so; that is readytelift the moment the rocl -"isx V 8 for'th'e lifting operatioiif In the accompanying drawing e gEig; I i-s-tt perspetivei iew showing the jeek" i nitscol lazpsed position just as it; is

abeilt to be Fig 2 sho-Wsthe position it instaintly as sumes on being; slightly pi essecv up against thewle; I I

Figz' 'is a section tl iroifglfo the j aek ajs-showir 4 is a11 enlergeel sectional detail showing the top. 01 the jack in se'ction and thetripin elevation; H i 1 r g: 5=is aivi-ew showing am ztppl'ication ofi my iiiventien tozthe.erd imrytype of level" Fig: 6' shows the various parts of" this jack disassembleda v j r IiI-tlieeon'struction shown iq 1'--FigSfi1-' to" 43 A represents the base of the iaek;end l" is e) hollow pestrising from its center and having; '21 slot: 2 in one side. The numeral 3 rep; resents inner tube fitted to r and tele's'e'opii c'a lily, connected with: the"hol IoW- post 1, and thisi tithe has a row" of ratchet-teeth- 4 protrialling; thneughi the slot filll'di a gravity pawl 5 W'ltlls a; Weighted: handle is held: non mall-yin contact" with: these. ratchet teeth m Thenumeral'? is aaserewtlie of pressed underf an a/xle-ffrem' bee V i otherob feet-tobeTiitedl'uponithetri y ;tr1pis provided with a cateh In) atit's lower ma lly raised. positi oiras which have a comparatively. slight pitch, shown in Fig. -an'd this screw is fitted tomove'up ahd.dOWIl lI1 thetube as-is the hollow-post 1 to" slide upon. the-tube 3'. head? is" mounted: upon: the upper}end jof the screw-'57, as viewed l'Ii Fig.*4%, t0 receive and sustain. the Weight o'f the objeet' 'te "be lifted, as illustrated in Figs;.-1 a'i 'd'2. l 1

A bevel gee'rQ is'lprovideclt'withinternal serewdzhreads" 10f Which-register withrfthe threads of the screw-7, andfhegear' 9 rests and; turns upon the upperjendl 'Q Z' theItLmbe 3 as illustrated in: Fig}. 3, 2111012 this gear 9 is turned by: drivingrgearq l'ly"supported by the tube which gear lly isturneiby 'the rocl 12 which is the means emial'oyedibythe operator to raise the: load by turning-the gear 9- Y around the screw which eztuses the: lat-Ii v ter to raise ortlowervaceordingi to, the way the actuating-rod 126's turneda t A trip-l3 is pivot-ed at 1'4; a t one side of; the head iii position; to retire Vint'othe recess 15' termed thlereoizer',.: l shown. in. 4 when? upward pressure is-=.appliizcl to the le er V v end, which is edzeptedto' engage' the shoiilde r 17 o'iiathe braeket'l 8 Whihh supportsthe pawl 5, and 9;- spring? 19 holds thetriiayih its new will: be" seen by m ferrin g toFig". 41 v Assi nnigthe jeek; to he in its norma'l'ly closed or collapsed state, as SliQWn inFig: "1, that is to say withthe teleseopiememliersell locked togethe'r'bytlie engagemeiitof the latch 16 heneaththeshoulder 176 th me 1e l etc 18 511-1 1 the; opereto ,h todo is tell his hands on therod aiicl raise against the axle or: Qbjecttdbelifte l f jacked, with the trip b'eneethaiicl -a'gaianstc Q- ohjectiwitlijust a slight upward pressure that is enough tooveifconie the :tensio -q f-ithe; v spiralspring, l9 with the'result. that the trip,

is pressecl down into the recess 15, assh -0 riat 2-,. causingthe; catch: lfifto pull away from the shoulder; 1 7 a'sshotvn in 2. This release causes the instantaneous deep of thebaseto the ground, the pawli5irlitliiig oven the? teeth r' timclstheiirlockingiinto the 160 i The of the jack with the thing to be lifted is the only brief preliminary to the actual lifting of the article.

To lower the load, the rod 12 is turned in the reverse direction until the loadis supported on the ground or floor, and then by raising .theihandle 6. until the pawl isremoved from the teeth, it permits the upper part of the jack, including the tube 3', the

screw, the head, and thetrip, to drop back into the collapsed position shown in Fig. 1, by'gravity, due to the weight of said part.

, In Figs. 5 and 6, I have merely sought to illustrate the same invention asapplied to the ordinary type of lever-jack. I employ the same trip 13 pivoted to-the bar 20, the

catch 16 and the lug 17 The head is on the usual toothedbar 20 in this instance, and this is operated in the usual manner by the hand lever 21, the action upon the bar being made reversible as usual by the trigger 22.

The frame 23 in. this form of device is tele scopically mounted in a hollow post 2'4 mount- 7 ed on a base 25 and said frame 23 is provided with a set of ratchet-teeth 26, inwhich the pawl 27 engages, and the latter is controlled bv' the weighted lever 28. i This jack is applied in the samemanner as the jack illustrated in Figs. 1 to .4. The operator lifts it by means of the hand-lever, pressing some portion of the front 13 of'the trip 13 or the horn 13 against the surface of the object to belifted. This causes the hook 16 to become disengaged from. the lug 17 with the resultant drop of the base 25 and'the frame 24 to the ground, whereupon the tooth lower down on the ratchet teeth 26, and the operator now proceeds to raise it and lower the lever to lift the bar 20 in the usual fashion of this type ofjack.

novelty andadvantagein my invention over the prior art resides in the time-saving element, dueto the instantaneous dropping of the base'of the ack through the space interveningfrom the object to be lifted to the ground or floor, in that way eliminating the usual lost motion of first adjusting the ack to thisspace by the screw or lever method as e a preliminary step to the application of lift-.

ing power.

Obviously the results may be obtainedby a backward pull or push upon some part of the trip.

I claim:

1. A lifting-ja k including slidably con- I awl 27 engages a In other words, I consider that the real nected members, a trip connecteclwith one of said members, and having a catch in position to engage the other member, whereby to hold Y the'members in closed adjustment, a portion of said trip located in position to engage the object to be lifted, thereby causing the release of the catch from the other member and permitting it to drop bylgravity to the ground or floor. j r

2. A lifting-j ack including telescopic meme bers, a trip connected with one of said members, and having a catch in position to engage the other member, whereby to hold the members in closed adjustment, a portion of said trip located in position to engage the object.

to be lifted, thereby. causing the relejaseof the catch from the other member and permitting it to drop by gravity to-theground or floor, and means for automatically locking the-members in the extended relation.

3.=A. lifting-jack including telescopic members, a trip, connected with one of said 7 members, and having a catch in pos tion to engage theother member, wherebyv to hold the members in closed adjustment, a portion of said trip located in position to'engage the object to be lifted, thereby causing the release of the catch from the other member and permitting it to drop by gravity to the ground or floor, means for automatically locking the members in the extended relation, and independent means for raising one of the mem; ber's. r H

4:. A lifting-jack including telescopic members, independent means forlocking the j 1'00" vmembers in closed and in extended ad ustment, one of said lockingmeans located gin position to engage the object to be lifted,

whereby to unlock the membersand permit the lower one to drop to the ground or floor,

the other lock acting automatically to hold. the members, in this extended position, and

manual means. for lengthening the jack to; apply li-ftingjpower to the object to be raised. 5. A lifting-jack including two telescopic members slidably connected, a head, means for raisingand lowering said head, a trip having means for automatically locking'the two members when in closed position, said trip extending into the head and projecting. thereabove in position to engage the object to be I lifted in: advance ofthe head, whereby to cause a release of the locked members and permit the lower member to drop to the ground or.

V 6. A lifting-jack including two telescopic members slidably connected, a head, means for raising andlowering said head, a'trip having means for automatically locking the two members when in closed position, said trip extending into the head and projecting thereabove in position to engage the object .to be lifted in advance of the head, whereby to cause a release'of the locked members and permit the lower member to drop to the groundfor floor, and a gravity pawl for auto- 7 matically locking the telescopic members in their extended position. l 7. A portable'lifting-jack including slidably connected members, a trigger for hold I ing said members together, 7 said trigger adapted to be released by pressure against the object to be lifted, whereby the lower memher is permitted to drop instantaneously to the ground or floor by gravity.

8. A lifting ack including members longitudinally movable relative to each other, and means normally holding said members against extending action, saidmeans beingreleased by engagement with the object to be lifted, V

9. A lifting jack including members slidably mounted relative to each other, and means normally holding said members against extending action, said means being released by engagement with the object to be'lifted to permit the jack to-be extended between the object to be lifted and the floor or ground.

- 10. A lifting jackincluding members slid ablymounted relative to each other, one of 7 said members having a head, and means associated with the head in position to engage an object to be lifted slightly in advance of the engagement thereof by the-head for allowing the jack to be extended between theobject to be lifted and the floor or ground.

11. A jack of the character described including members movable relative to' each 7 other for lengthening action, and meansv associated with sad members for normally pre- 5 venting an extending movement of said members and to be released by the object to be lifted when the jack is in lifting position to allow at least one of said members to drop downward. r y f 40 .12. A jack of the character described including members slidably connected together, and means for normally preventing relative extending action of said members, said members being extended upon the release of said means by the object to be lifted.

13. A jack of the character described including members slidably connected together, a catch for normally holding said members against relative extending action, and means for immediately releasing said catch when the jack is in position to engage a. load to allow at least oneof said members to drop downward to approximately closeup the space between V the object to be lifted and the floor or ground.

14. A jack of thecharacter described including members sli dably connected together, a trigger connected with one member and in a position to contact with the object to be lifted in advance of the jack, whereby to cause so a release of the members of the jack to permit I the lower member to immediately extend to the supporting surface below.

In testimony whereof -I aflix my signature.

J OHN ALBERT CHEAPE. 

